The invention relates to labeling machines in which labels are continuously or intermittently transferred from a web to articles, and relates in particular to labeling machines in which labels are checked and, if necessary, redirected so that unwanted labels are not applied to articles.
For example, U.S. Pat. No. 3,772,123 discloses a label reject mechanism for a labeling machine that includes a pinch wheel on an actuated arm that selectively engages incorrect labels between the pinch wheel and a rotating wheel, preventing them from being applied to a vacuum actuator drum.
U.S. Pat. No. 5,405,482 discloses a labeling machine that includes a label scanning unit for scanning labels on a web, as well as a label removal unit that includes a single freely rotating roller. If an incorrect label is detected by the label scanning unit, then the incorrect label is removed from a rotating label applicator drum by having the label removal unit advance the roller into contact with the adhesive side of the incorrect label on the applicator drum. The incorrect label would then be removed from the roller.
U.S. Pat. No. 6,841,018 also discloses a labeling machine including a label reconciliation device that selectively advances actuating arm that terminates in a roller toward incorrect labels while on a vacuum drum 7. The reconciliation device further includes a reject label web onto which rejected labels are applied so that they are removed from the label application assembly.
U.S. Pat. No. 6,450,227 discloses a labeling machine that includes a label check station having an actuator for moving a casing from a rest position that does not interrupt the normal direction of flow of a web of labels to a working position that changes the direction of flow of the web of labels so that the incorrect label may be directed off of the web and onto a rotating reject label core.
Conventional label reject systems, however, generally either remove labels from an applicator drum, or change the direction of travel of a web prior to reaching an applicator stage. Changing the direction of travel of a web to remove labels typically changes the path length of web in order to remove the rejected label from the web. Even small changes in a path length, however, can adversely affect the performance of a labeling machine that relies on high speeds and precision timing.
There is a need, therefore, for an improved label removal system that more efficiently and effectively removes labels from a web.